1. Field of the Invention
The present invention relates to a circularly polarizing plate and a bendable display device including a circularly polarizing plate.
2. Description of the Related Art
Conventionally, in order to suppress adverse effects caused by reflection of external light, a circularly polarizing plate has been used for a display device.
On the other hand, in recent years, there has been an increasing demand for making an image display element, represented by an organic electroluminescence (EL) element, flexible (bendable). Further, there has been a demand for not just realization of flexibilization but realization of flexibilization at a very small radius of curvature.
However, in a case in which an organic EL display device is bent at a very small radius of curvature, a great force is applied to a phase difference film of a circularly polarizing plate (a tensile force is applied to some parts and a compressive force is applied to other parts), a phase difference in the parts is changed.
In JP2014-170221A, in order to solve the above problem, there is provided a circularly polarizing plate including a phase difference film exhibiting predetermined optical properties, in which a slow axis direction of the phase difference film is adjusted to define an angle of 20 to 70 degrees with respect to a bending direction of a display device. In JP2014-170221A, as the phase difference film exhibiting predetermined optical properties, a resin film such as PURE-ACE WR (polycarbonate resin film) is used.